AD 81-21-51 R1
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Martin Corporation | L-1011-385-1 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-1-14 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-1-15 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-3 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
Unsafe Condition
Failure of the Airborne Vibration Monitor (AVM) System to alert flight crews to engine abnormalities, such as sudden vibration increases or oil filter pressure light illumination, could lead to undetected engine failure or malfunction.
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Required Actions
Revise the Airplane Flight Manual to include AVM system operational requirements and emergency procedures, reactivate AVM input to the ENG/APU STATUS light, comply with specified service bulletins, and perform maintenance actions when specified AVM or oil pressure indications occur.
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Compliance Time
Within 25 hours time in service after receipt of this AD or within 3 calendar days, whichever occurs later for paragraph A; within 25 hours time in service for paragraph B; within 75 days calendar time after receipt for paragraph C.
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Affected Aircraft
Lockheed-California Company Model L-1011-385 series airplanes, including L-1011-385-1, L-1011-385-1-14, L-1011-385-1-15, and L-1011-385-3, certificated in all categories.
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Federal Register Abstract
Powerplant Limitations
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_81-21-51_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-21-51 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes Subject: Powerplant Limitations Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/17/1983 Make: Lockheed Martin Corporation Model: L-1011-385-1 | L-1011-385-1-14 | L-1011-385-1-15 | L-1011-385-3 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-21-51 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4533 AD NUMBER: 81-21-51 R1 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes ACTION: SUMMARY: DATES: Effective January 17, 1983. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-21-51 R1 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-4329 as amended by Amendment 39-4533. Applies to Lockheed Model L-1011-385 series airplanes, certificated in all categories. To alert the flight crew to conditions which may precede engine failure, perform the following, unless previously accomplished: A. Within 25 hours time in service after the receipt of this AD or within 3 calendar days, whichever occurs later, revise the Lockheed L-1011 FAA approved Airplane Flight Manual LR-25925 to add the following and provide to flight crews: NOTE: FAA approved Lockheed L-1011 Airplane Flight Manual revision dated September 29, 1981, is considered an acceptable means of compliance for paragraph A. SECTION 1 - LIMITATIONS POWERPLANT LIMITATIONS Airborne Vibration Monitor (AVM) System o At least one channel (A or B) (FAN or TURB) of the AVM System must be operative for each engine for all flight operations. o The operative AVM channel (A or B) (FAN or TURB) must be the same for all engines and must be latched in. o When both channels of the AVM System are operative, channel A or FAN must be latched in. If this channel becomes inoperative (indication goes to zero) inflight, select B or TURB. o For single or dual channel operation, the AVM filter selector must be set to the NORM position. SECTION 2 - EMERGENCIES ENGINE ABNORMAL VIBRATION INDICATION. During steady running conditions, if an Airborne Vibration Monitor (AVM) System channel indicates a sudden increase of 1 unit or more, or exceeds 2.5 units (warning light setting) for more than 2 seconds, even if the indication returns to normal: IMMEDIATE ACTION THROTTLE Close FUEL AND IGNITION SWITCH Off NOTE During takeoff roll, a momentary fluctuation of the AVM indication with no other indication of engine malfunction is not cause for engine shutdown. REFERENCE HYDRAULIC POWER Check ELECTRICAL LOADS Monitor AC ESSENTIAL POWER Check Do not attempt a relight unless a greater emergency exists. NOTE When holding or descending in heavy icing conditions, the AVM indication may gradually increase to above 2.5 units (warning light setting). No action is required unless other indications of engine malfunction are observed. This condition can be alleviated by increasing N1 to 90 percent for 5 seconds when ice accumulation (gradual vibration increase) is first detected. SECTION 2 - EMERGENCIES ENGINE OIL FILTER PRESSURE LIGHT ILLUMINATED If the engine oil FILTER PRESSURE light illuminates steadily: IMMEDIATE ACTION THROTTLE Close FUEL AND IGNITION SWITCH Off REFERENCE HYDRAULIC POWER Check ELECTRICAL LOADS Monitor AC ESSENTIAL POWER Check Do not attempt a relight unless a greater emergency exists. B. Within 25 hours time in service after the receipt of this AD, reactivate the AVM input to the ENG/APU STATUS light in accordance with the Accomplishment Instructions in Lockheed L-1011 Alert Service Bulletin 093-77-A044, Revision 2, dated September 29, 1981, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. C. Within 75 days calendar time after receipt of this AD, comply with paragraphs A and B (Parts I and II) of the Accomplishment Instructions in Lockheed L-1011 Alert Service Bulletin 093-77-A049 dated September 29, 1981, or Revision 1, dated October 13, 1981, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. D. When the indications specified in paragraph A above occur, engines must undergo the following appropriate maintenance actions prior to further engine operation for flight: 1. Rolls Royce Alert Service Bulletin RB.211-77-A6422 dated September 4, 1981, paragraph D.(3) for oil pressure and/or AVM indications. 2. Lockheed L-1011 Maintenance Manual Chapter 71-91-00, High Indicated Vibration. E. For aircraft incorporating engines which are in compliance with AD 82-12-05, Amendment 39-4398, and which have engine indicating systems modified in accordance with the Accomplishment Instructions in Lockheed L-1011 Service Bulletin 093-77-052, dated December 17, 1982, the Powerplant Limitations and Emergency Procedures contained in FAA approved Lockheed L-1011 Airplane Flight Manual No. LR-25925 revision dated December 20, 1982, may be used in lieu of those specified in paragraph A. above. F. Special flight permits for a two-engine ferry flight may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. G. Alternate methods of compliance with this AD which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Lockheed-California Company, P.O. Box 551, Burbank, California 91520, Attention: Commercial Support Contracts, Dept. 63-11, U-33, B-1. These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California. Amendment 39-4329 became effective March 11, 1982, to all persons, except those to whom it was made immediately effective by Telegraphic AD T81-21-51, dated October 1, 1981. This Amendment 39-4533 becomes effective January 17, 1983. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_81-21-51_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-21-51 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes Subject: Powerplant Limitations Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/17/1983 Make: Lockheed Martin Corporation Model: L-1011-385-1 | L-1011-385-1-14 | L-1011-385-1-15 | L-1011-385-3 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-21-51 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4533 AD NUMBER: 81-21-51 R1 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes ACTION: SUMMARY: DATES: Effective January 17, 1983. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-21-51 R1 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-4329 as amended by Amendment 39-4533. Applies to Lockheed Model L-1011-385 series airplanes, certificated in all categories. To alert the flight crew to conditions which may precede engine failure, perform the following, unless previously accomplished: A. Within 25 hours time in service after the receipt of this AD or within 3 calendar days, whichever occurs later, revise the Lockheed L-1011 FAA approved Airplane Flight Manual LR-25925 to add the following and provide to flight crews: NOTE: FAA approved Lockheed L-1011 Airplane Flight Manual revision dated September 29, 1981, is considered an acceptable means of compliance for paragraph A. SECTION 1 - LIMITATIONS POWERPLANT LIMITATIONS Airborne Vibration Monitor (AVM) System o At least one channel (A or B) (FAN or TURB) of the AVM System must be operative for each engine for all flight operations. o The operative AVM channel (A or B) (FAN or TURB) must be the same for all engines and must be latched in. o When both channels of the AVM System are operative, channel A or FAN must be latched in. If this channel becomes inoperative (indication goes to zero) inflight, select B or TURB. o For single or dual channel operation, the AVM filter selector must be set to the NORM position. SECTION 2 - EMERGENCIES ENGINE ABNORMAL VIBRATION INDICATION. During steady running conditions, if an Airborne Vibration Monitor (AVM) System channel indicates a sudden increase of 1 unit or more, or exceeds 2.5 units (warning light setting) for more than 2 seconds, even if the indication returns to normal: IMMEDIATE ACTION THROTTLE Close FUEL AND IGNITION SWITCH Off NOTE During takeoff roll, a momentary fluctuation of the AVM indication with no other indication of engine malfunction is not cause for engine shutdown. REFERENCE HYDRAULIC POWER Check ELECTRICAL LOADS Monitor AC ESSENTIAL POWER Check Do not attempt a relight unless a greater emergency exists. NOTE When holding or descending in heavy icing conditions, the AVM indication may gradually increase to above 2.5 units (warning light setting). No action is required unless other indications of engine malfunction are observed. This condition can be alleviated by increasing N1 to 90 percent for 5 seconds when ice accumulation (gradual vibration increase) is first detected. SECTION 2 - EMERGENCIES ENGINE OIL FILTER PRESSURE LIGHT ILLUMINATED If the engine oil FILTER PRESSURE light illuminates steadily: IMMEDIATE ACTION THROTTLE Close FUEL AND IGNITION SWITCH Off REFERENCE HYDRAULIC POWER Check ELECTRICAL LOADS Monitor AC ESSENTIAL POWER Check Do not attempt a relight unless a greater emergency exists. B. Within 25 hours time in service after the receipt of this AD, reactivate the AVM input to the ENG/APU STATUS light in accordance with the Accomplishment Instructions in Lockheed L-1011 Alert Service Bulletin 093-77-A044, Revision 2, dated September 29, 1981, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. C. Within 75 days calendar time after receipt of this AD, comply with paragraphs A and B (Parts I and II) of the Accomplishment Instructions in Lockheed L-1011 Alert Service Bulletin 093-77-A049 dated September 29, 1981, or Revision 1, dated October 13, 1981, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. D. When the indications specified in paragraph A above occur, engines must undergo the following appropriate maintenance actions prior to further engine operation for flight: 1. Rolls Royce Alert Service Bulletin RB.211-77-A6422 dated September 4, 1981, paragraph D.(3) for oil pressure and/or AVM indications. 2. Lockheed L-1011 Maintenance Manual Chapter 71-91-00, High Indicated Vibration. E. For aircraft incorporating engines which are in compliance with AD 82-12-05, Amendment 39-4398, and which have engine indicating systems modified in accordance with the Accomplishment Instructions in Lockheed L-1011 Service Bulletin 093-77-052, dated December 17, 1982, the Powerplant Limitations and Emergency Procedures contained in FAA approved Lockheed L-1011 Airplane Flight Manual No. LR-25925 revision dated December 20, 1982, may be used in lieu of those specified in paragraph A. above. F. Special flight permits for a two-engine ferry flight may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. G. Alternate methods of compliance with this AD which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Lockheed-California Company, P.O. Box 551, Burbank, California 91520, Attention: Commercial Support Contracts, Dept. 63-11, U-33, B-1. These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California. Amendment 39-4329 became effective March 11, 1982, to all persons, except those to whom it was made immediately effective by Telegraphic AD T81-21-51, dated October 1, 1981. This Amendment 39-4533 becomes effective January 17, 1983. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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